feat: [Foundry] Fetch HIP-719 remote state for fungible tokens

@hts-forking/test/data/MFCT/getTokenRelationship_0xa3612a87022a4706fc9452c50abd2703ac4fd7d9.json

@@ -0,0 +1,16 @@
+{
+    "tokens": [
+        {
+            "automatic_association": false,
+            "balance": 5000,
+            "created_timestamp": "1724382479.562855337",
+            "decimals": 0,
+            "token_id": "0.0.4730999",
+            "freeze_status": "NOT_APPLICABLE",
+            "kyc_status": "NOT_APPLICABLE"
+        }
+    ],
+    "links": {
+        "next": null
+    }
+}

@hts-forking/test/data/USDC/getTokenRelationship_0x0000000000000000000000000000000000001438.json

@@ -0,0 +1,16 @@
+{
+    "tokens": [
+        {
+            "automatic_association": false,
+            "balance": 5000000,
+            "created_timestamp": "1706825561.156945003",
+            "decimals": 6,
+            "token_id": "0.0.429274",
+            "freeze_status": "UNFROZEN",
+            "kyc_status": "NOT_APPLICABLE"
+        }
+    ],
+    "links": {
+        "next": null
+    }
+}

scripts/curl

@@ -84,6 +84,21 @@ for (const [re, fn] of /** @type {const} */([
             return undefined;
         }
     }],
+    [/^accounts\/((0x[0-9a-fA-F]{40})|(0\.0\.\d+))\/tokens/, idOrAliasOrEvmAddress => {
+        assert(typeof idOrAliasOrEvmAddress === 'string');
+        const tokenId = searchParams.get('token.id');
+        assert(tokenId !== null);
+
+        const token = tokens[tokenId];
+        if (token === undefined)
+            return { tokens: [], links: { next: null } };
+
+        try {
+            return require(`../@hts-forking/test/data/${token.symbol}/getTokenRelationship_${idOrAliasOrEvmAddress.toLowerCase()}.json`);
+        } catch {
+            return undefined;
+        }
+    }],
 ])) {
     const match = endpoint.match(re);
     if (match !== null) {

src/HtsSystemContractJson.sol

@@ -423,6 +423,15 @@ contract HtsSystemContractJson is HtsSystemContract {
         return slot;
     }
 
+    function _isAssociatedSlot(address account) internal override returns (bytes32) {
+        bytes32 slot = super._isAssociatedSlot(account);
+        if (vm.load(_scratchAddr(), slot) == bytes32(0)) {
+            bool associated = mirrorNode().isAssociated(address(this), account);
+            _setValue(slot, bytes32(uint256(associated ? 1 : 0)));
+        }
+        return slot;
+    }
+
     function _setValue(bytes32 slot, bytes32 value) private {
         vm.store(address(this), slot, value);
         vm.store(_scratchAddr(), slot, bytes32(uint(1)));

src/IMirrorNodeResponses.sol

@@ -39,4 +39,14 @@ interface IMirrorNodeResponses {
         int64 amount;
         string denominating_token_id;
     }
+
+    struct TokenRelationship {
+        bool automatic_association;
+        uint256 balance;
+        string created_timestamp;
+        uint256 decimals;
+        string token_id;
+        string freeze_status;
+        string kyc_status;
+    }
 }

src/MirrorNode.sol

@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: Apache-2.0
 pragma solidity ^0.8.0;
 
+import "./IMirrorNodeResponses.sol";
 import {Vm} from "forge-std/Vm.sol";
 
 abstract contract MirrorNode {
@@ -25,6 +26,8 @@ abstract contract MirrorNode {
 
     function fetchAccount(string memory account) external virtual returns (string memory json);
 
+    function fetchTokenRelationshipOfAccount(string memory account, address token) external virtual returns (string memory json);
+
     function getBalance(address token, address account) external returns (uint256) {
         uint32 accountNum = _getAccountNum(account);
         if (accountNum == 0) return 0;
@@ -51,6 +54,17 @@ abstract contract MirrorNode {
         return 0;
     }
 
+    function isAssociated(address token, address account) external returns (bool) {
+        try this.fetchTokenRelationshipOfAccount(vm.toString(account), token) returns (string memory json) {
+            if (vm.keyExistsJson(json, ".tokens")) {
+                bytes memory tokens = vm.parseJson(json, ".tokens");
+                IMirrorNodeResponses.TokenRelationship[] memory relationships = abi.decode(tokens, (IMirrorNodeResponses.TokenRelationship[]));
+                return relationships.length > 0;
+            }
+        } catch {}
+        return false;
+    }
+
     function getAccountAddress(string memory accountId) external returns (address) {
         if (bytes(accountId).length == 0
             || keccak256(bytes(accountId)) == keccak256(bytes("null"))

src/MirrorNodeFFI.sol

@@ -60,6 +60,15 @@ contract MirrorNodeFFI is MirrorNode {
         ));
     }
 
+    function fetchTokenRelationshipOfAccount(string memory idOrAliasOrEvmAddress, address token) external override returns (string memory) {
+        return _get(string.concat(
+            "accounts/",
+            idOrAliasOrEvmAddress,
+            "/tokens?token.id=0.0.",
+            vm.toString(uint160(token))
+        ));
+    }
+
     /**
      * @dev Returns the block information by given number.
      *

test/IHRC719.t.sol

@@ -65,4 +65,23 @@ contract IHRC719TokenAssociationTest is Test, TestSetup {
 
         vm.stopPrank();
     }
+
+    function test_IHRC719_with_real_accounts() external {
+        if (testMode() == TestMode.JSON_RPC) {
+            // TODO: Enable this test with https://github.com/hashgraph/hedera-forking/issues/126
+            return;
+        }
+        vm.startPrank(USDC_TREASURY);
+        assertEq(IHRC719(USDC).isAssociated(), true);
+        assertEq(IHRC719(USDC).dissociate(), 1);
+        assertEq(IHRC719(USDC).isAssociated(), false);
+
+
+        vm.startPrank(MFCT_TREASURY);
+        assertEq(IHRC719(MFCT).isAssociated(), true);
+        assertEq(IHRC719(MFCT).dissociate(), 1);
+        assertEq(IHRC719(MFCT).isAssociated(), false);
+
+        vm.stopPrank();
+    }
 }

test/lib/MirrorNodeMock.sol

@@ -43,4 +43,10 @@ contract MirrorNodeMock is MirrorNode {
         string memory path = string.concat("./@hts-forking/test/data/getAccount_", vm.toLowercase(account), ".json");
         return vm.readFile(path);
     }
+
+    function fetchTokenRelationshipOfAccount(string memory idOrAliasOrEvmAddress, address token) external override view returns (string memory) {
+        string memory symbol = _symbolOf[token];
+        string memory path = string.concat("./@hts-forking/test/data/", symbol, "/getTokenRelationship_", vm.toLowercase(idOrAliasOrEvmAddress), ".json");
+        return vm.readFile(path);
+    }
 }